This invention is related to rings for furnace rolls and to a ringless furnace roll, and more particularly to a composite roll, and a composite ring each having a rim that is centrifugally cast of a material that is relatively insoluble with respect to the steel strip being transferred from the furnace, and an inner liner of a material having different solubility characteristics than the rim. The liner and the rim are centrifugally cast to fuse the liner to the rim.
In my U.S. Pat. No. 5,338,280, issued Aug. 16, 1994, for "Annealing and Tunnel Furnace Rolls", I disclosed a novel furnace roll for transferring a heated strip of a steel alloy from an annealing furnace. The roll employs a series of spaced rings that are welded to a tubular body. The rings are formed of a steel alloy selected so as to be relatively non-weldable with respect to the steel alloy of the heated strip as a consequence of the high covalent bonded alloy particles concentration. The reason is to reduce the usual pick-up or material transfer between the roll and the strip caused by the tendency of the strip material to adhere to the rings at high temperatures, thus reducing the life of the rings and the quality of the strip.
However, a ring material that is relatively insoluble with the strip material is usually difficult to weld to the furnace roll body because of its' high adhesion and solubility resistance.